Wiring substrate, electronic device, and electronic module each having plate-shaped conductive portion in frame portion of insulation substrate

ABSTRACT

To provide a wiring substrate, an electronic device, and an electronic module the size of which can be easily reduced and the strength of which can be maintained. A wiring substrate includes an insulation substrate and an electrical wiring structure. The insulation substrate includes a recess section in one surface. A frame portion of the insulation substrate that forms a side surface which connects an opened surface and a bottom surface of the recess section to each other includes a first conductive portion having a plate shape in the frame portion.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.16/957,616, filed Jun. 24, 2020 which is based upon and claims benefitof priority from International Patent Application No.:PCT/JP2018/048106, filed Dec. 27, 2018, which is based upon and claimsbenefit from Japanese Patent Application Nos.: 2018-014673, filed Jan.31, 2018 and 2017-253148, filed Dec. 28, 2017, the entire contents ofwhich are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a wiring substrate, an electronicdevice, and an electronic module.

BACKGROUND ART

There is a package-shaped wiring substrate that accommodates anelectronic component therein and allows the electronic component thereinto be connected to external wiring so as to be mounted. If theelectronic component is connected to an electronic device through thewiring substrate, handling, wiring, and connection of the electroniccomponent are facilitated. If the electronic component is sealed with alid, the electronic component is isolated from an external environment.Thus, the electronic component can be more stably operated.

A wiring substrate widely used as the above-described wiring substrateincludes a recess section-shaped accommodation section to accommodatethe electronic component. This wiring substrate is provided with awiring conductor that penetrates from inside to outside of theaccommodation section to electrically connect the electronic componentin the accommodation section to the outside.

There also is a structure in which the lid or the like that seals theaccommodation section is formed of a metal conductor, and the lid joinedby using a through via disposed in a side wall of the accommodationsection is connected to an electrode at a surface opposite the lid. Withthis structure, if a ground voltage is supplied to the electrode,influence of noise on the inside is reduced (see Japanese UnexaminedPatent Application Publication No. 2000-312060 and 2009-111124).

SUMMARY OF INVENTION

A wiring substrate according to an aspect of the present disclosureincludes an insulation substrate that comprises a recess section in afirst surface and an electrical wiring structure.

A frame portion of the insulation substrate that forms a side surfacewhich connects an opened surface and a bottom surface of the recesssection to each other comprises a first conductive portion having aplate shape in the frame portion.

A wiring substrate according to another aspect of the present disclosureincludes

an insulation substrate that comprises a recess section in a firstsurface and

an electrical wiring structure.

A frame portion of the insulation substrate that forms a side surfacewhich connects an opened surface and a bottom surface of the recesssection comprises a first conductive portion in the frame portion.

A distance between the first conductive portion and an inner sidesurface of the recess section is greater at a bottom surface height ofthe recess section than on a first surface side.

An electronic device according to an aspect of the present disclosureincludes

the above-described wiring substrate and

an electronic component that is disposed in the recess section and thatis connected to the electrical wiring structure.

An electronic module according to an aspect of the present disclosureincludes

the above-described electronic device and

a module substrate to which the electronic device is connected.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is an overall perspective view of a wiring substrate with a lidremoved.

FIG. 1B is a perspective view of the wiring substrate seen from a bottomsurface side.

FIG. 2A is a plan view of the wiring substrate.

FIG. 2B is a sectional view of an electronic module.

FIG. 3 is a sectional view including a wiring conductor.

FIG. 4 is a see-through perspective view of wiring from a frame-shapedmetalized layer to an external connection conductor.

FIG. 5A is an explanatory view of a first variation of a firstconductive portion.

FIG. 5B is an explanatory view of a second variation of the firstconductive portion.

DESCRIPTION OF EMBODIMENTS

An embodiment according to the present disclosure is described belowwith reference to the drawings.

FIGS. 1A and 1B are overall perspective views of a wiring substrate 100of the present embodiment with a lid 120 removed. FIG. 1A illustrates asurface on a side where the lid 120 is to be joined, and FIG. 1Billustrates a surface opposite the side where the lid 120 is joined.

The wiring substrate 100 is an electronic component accommodationpackage that includes, for example, an insulation substrate 110, the lid120, and a conductive portion including an electrical wiring structure.The insulation substrate 110 includes, for example, a frame portion 110a (side walls) and a base portion 110 b. The insulation substrate 110has an accommodation section 111 (recess section) that is a depressedregion in a recessed shape in the surface where the lid 120 is to bejoined (a sealing surface, that is, an upper surface in the zdirection). The accommodation section 111 accommodates an electroniccomponent 150. The frame portion 110 a forms side surfaces (inner sidesurfaces s1) that surround the accommodation section 111 other than anopened surface superposed on the sealing surface and a surface oppositethe opened surface (a placement surface for the electronic component150). That is, the frame portion 110 a forms surfaces connecting theopened surface and a placement surface s3 (bottom surface of thedepressed region) to each other and separates the accommodation section111 and an external environment from each other. Here, the inner sidesurfaces s1 are each parallel to the z direction. This ensures a largespace between the opened surface and the placement surface s3 of theaccommodation section 111. A frame-shaped metalized layer 112(frame-shaped conductive layer) is disposed at a first surface s11 (endsurface on the opened surface side) serving as a joining surface of theframe portion 110 a with the lid 120. The frame-shaped metalized layer112 is joined to the lid 120 with a sealing material such as a silverbrazing alloy. Although it is not particularly limited, here, the sizeof the insulation substrate 110 is as follows: a side in an xy plane isabout 0.8 to 10.0 mm and the thickness in the z direction is about 0.2to 2.0 mm.

The base portion 110 b forms the placement surface s3 (bottom surface)of the accommodation section 111 and a second surface s12 (bottom ofsubstrate) that serves as a mounting surface for mounting on a modulesubstrate 200. The base portion 110 b has a plate-shaped form parallelto the xy plane. The base portion 110 b includes a pair of connectionpads 114 on the placement surface s3. External connection conductors 116are disposed at the second surface s12 of the base portion 110 bopposite the placement surface s3. The connection pads 114 have asurface shape and are electrically connected to the external connectionconductors 116 through conductors 115 that penetrate through the baseportion 110 b (see FIG. 2B).

The electronic component 150 is attached to the connection pads 114. Forelectrical connection between the electronic component 150 and theconnection pads 114, a joining material 160 such as a conductiveadhesive (for example, resin to which silver or other conductiveparticles are added) is used. If the joining material 160 isthermosetting, the joining material 160 is applied to the connectionpads 114 in advance, and heat is applied with the electronic component150 positioned relative to the connection pads 114 (joining material160). Thus, the joining material 160 is cured, and the electroniccomponent 150 is connected to the connection pads 114 through thejoining material 160. The connection pads 114 are formed convexly fromthe placement surface s3 by, for example, screen printing (printing) orthe like. Thus, the electronic component 150 is secured and separatedfrom the placement surface s3 in the accommodation section 111. If theelectronic component 150 generates, for example, vibration duringoperation, the thickness of the connection pads 114 and the joiningmaterial 160 can be determined such that the electronic component 150 isaccommodated in the accommodation section 111 without being brought intocontact with the placement surface s3 and the lid 120 during vibration.

The external connection conductors 116 are external electrodes to bejoined to electrode pads 201 of the module substrate 200 (see FIG. 2B).An electronic device 10 that includes the wiring substrate 100 and theelectronic component 150 accommodated in the wiring substrate 100 isincluded in an electronic module 1 (see FIG. 2B) together with themodule substrate 200 (see FIG. 2B) to which the external connectionconductors 116 are joined. Examples of the electronic component 150include, but not limited to, for example, a crystal resonator, a surfaceacoustic wave element (SAW filter), or the like. Any one of a variety ofelectronic components such as a piezoelectric element, a capacitiveelement, a resistance element, an inductor for other purposes, anothersemiconductor element, and so forth may be used. A plurality ofelectronic components may be accommodated in a single accommodationsection 111 according to need.

The insulation substrate 110 has insulation properties and is formed ofa ceramic material, such as, for example, an aluminum oxide-basedsintered body, an aluminum nitride-based sintered body, a mullite-basedsintered body, or a glass-ceramic sintered body. Here, it is assumedthat the insulation substrate 110 is formed of an aluminum oxide-basedsintered body (alumina-based sintered body) for description. The frameportion 110 a and the base portion 110 b of the insulation substrate 110are integrally formed such that the placement surface s3 is positionedat a bottom surface height h1 of the accommodation section 111.

The lid 120 is formed of conductive metal and is joined to theframe-shaped metalized layer 112, thereby hermetically sealing theaccommodation section 111. For sealing, a conductive sealing member suchas AuSn or a silver brazing alloy is used. The lid 120 is grounded so asto suppress propagation of external noise into the accommodation section111. The lid 120 is connected to one of the external connectionconductors 116 of the insulation substrate 110 through the conductivesealing member, the frame-shaped metalized layer 112, and a wiringconductor 113. If the external connection conductor 116 connected to thelid 120 is grounded, the lid 120 is grounded.

The frame-shaped metalized layer 112 is formed of conductive metal. Theframe-shaped metalized layer 112 is formed on the first surface s11 ofthe frame portion 110 a by, for example, printing.

Exposed surfaces of the frame-shaped metalized layer 112, the connectionpads 114, the external connection conductors 116, and so forth may becoated with nickel-plated layers and/or gold-plated layers. For example,nickel-plated layers are provided on the exposed surfaces to a thicknessof 1 to 20 μm, and a gold-plated layers are provided on thesenickel-plated layers to a thickness of 0.1 to 3.0 μm. In this way,oxidation corrosion of the outer portions of the exposed surfaces issuppressed. With the plated layers, connection between the frame-shapedmetalized layer 112 disposed on an upper surface of the insulationsubstrate 110 that is an insulation body and the lid 120 that is a metalconductor can be facilitated and strengthened.

Next, electrical wiring of the wiring substrate 100 is described.

FIG. 2A is a plan view of the wiring substrate 100. FIG. 2B is asectional view of the electronic module 1 taken along line X1-X1including the connection pads 114 and the electronic component 150 inFIG. 2A.

As illustrated in FIG. 2A, the wiring conductor 113, which will bedescribed later, is disposed, so as to be superposed on the externalconnection conductor 116 to be grounded, in a region between one of theinner side surfaces s1 and one of the outer side surfaces s2 of theframe portion 110 a and a partial region of the base portion 110 b, forexample, in a region from a position superposed on the frame portion 110a toward the placement surface s3 in plan view. The wiring conductor 113is disposed close to the short side of a planar shape of the insulationsubstrate 110 in the frame portion 110 a. The wiring conductor 113 isincluded in a conductive portion of the wiring substrate 100 of thepresent embodiment.

As illustrated in FIG. 2B, the electronic module 1 is made by joiningthe electronic device 10 to the electrode pads 201 of the modulesubstrate 200 with joining members 210 such as solder interposedtherebetween. In the electronic device 10 (electronic module 1), theconnection pads 114 and the external connection conductors 116 areconnected to each other through the through conductors 115 thatpenetrate through the base portion 110 b. The electronic component 150operates in accordance with a voltage and/or a current applied to theexternal connection conductors 116. The connection pads 114, the throughconductors 115, and the external connection conductors 116 form theelectrical wiring structure of the wiring substrate 100 of the presentembodiment.

FIG. 3 is a sectional view taken along section line X2-X2 in FIG. 2A.

As described above, the wiring conductor 113 extends from the frameportion 110 a to the base portion 110 b in the insulation substrate 110.Here, in the wiring conductor 113, a first conductive portion 113 a thatextends from an upper portion of the frame portion 110 a in the zdirection and a second conductive portion 113 b that extends in the baseportion 110 b in the x direction are integrally connected. A thirdconductive portion 113 c is superposed on the external connectionconductor 116 in plan view seen in the z direction and connected to thesecond conductive portion 113 b.

The first conductive portion 113 a penetrates through the inside of theframe portion 110 a in the z direction without being exposed in theinner side surface s1 or the outer side surface s2 of the frame portion110 a. The first conductive portion 113 a is connected to a rear side(contact surface side in contact with the frame portion 110 a) of theframe-shaped metalized layer 112 on the first surface s11 side. Thesecond conductive portion 113 b is electrically connected to theexternal connection conductor 116 through the third conductive portion113 c. Thus, the lid 120 is electrically connected through the wiringconductor 113 not exposed in the surfaces of the insulation substrate110 from the frame-shaped metalized layer 112 to the external connectionconductor 116.

The accommodation section 111 sides of the first conductive portion 113a and the second conductive portion 113 b are coated with a coatinglayer 110 c. The coating layer 110 c is formed of the same material asthe material of the insulation substrate 110, that is, aluminumoxide-based ceramic paste here. In the wiring substrate 100, the coatinglayer 110 c is integral and continuous as part of the insulationsubstrate 110.

Here, relative to a tangent ml in contact with the first conductiveportion 113 a at an arbitrary point of contact P1, part of the firstconductive portion 113 a separated from the point of contact P1 in the zdirection is curved in a direction separating from the tangent m 1toward the accommodation section 111.

Regarding the distance between the first conductive portion 113 a andthe inner side surface s1 of the frame portion 110 a, a distance L4 atthe bottom surface height h1 of the accommodation section 111 is greaterthan distances L1 to L3 closer to the first surface s11 than the bottomsurface height h1 in the z direction. The distances L1 to L4 graduallyincrease from the first surface s11 side toward the bottom surfaceheight h1. Here, the first surface s11 side means a predeterminedportion close to the first surface s11 out of a region from the bottomsurface height h1 to the first surface s11. The first conductive portion113 a is inclined relative to a line v perpendicular to the secondsurface s12 at a degree of inclination r that is greater than a degreeof inclination of the inner side surface s1. The form of the firstconductive portion 113 a as described above appears in a predeterminedsection, that is, a section that intersects the inner side surface s1,the first surface s11, and the second surface s12 and extends along thefirst conductive portion 113 a.

The second conductive portion 113 b is gently continuously connected tothe first conductive portion 113 a and extends in a direction parallelto the placement surface s3 of the accommodation section 111. A largesurface of the second conductive portion 113 b is not necessarilyparallel to the placement surface s3. This large surface may be slightlyinclined or may be undulated.

FIG. 4 is a see-through perspective view of wiring from the frame-shapedmetalized layer 112 to the external connection conductor 116.

The first conductive portion 113 a and the second conductive portion 113b have respective plate shapes and curved surface shapes in which largesurfaces are curved. That is, the entirety of the first conductiveportion 113 a and the second conductive portion 113 b has a curvedsurface shape in which the orientation of the entirety of the firstconductive portion 113 a and the second conductive portion 113 bgradually changes. The large surfaces of the first conductive portion113 a and the second conductive portion 113 b are respectively orientedalong the inner side surface s1 and the placement surface s3. Here, theplate shape is not limited to a flat plate shape and may be a shapehaving a curved surface shape formed by being curved (belt shape or thelike).

The first conductive portion 113 a is connected to the frame-shapedmetalized layer 112 in a range in which the first conductive portion 113a extends in the y direction. The second conductive portion 113 b has anarea sufficiently large for the third conductive portion 113 c having acolumnar shape. Accordingly, connection is reliably made in a largerange from the frame-shaped metalized layer 112 to the externalconnection conductor 116. Since neither the first conductive portion 113a nor the second conductive portion 113 b is exposed in the surfaces ofthe insulation substrate 110, an unintentional short circuit is notmade. If the exposed surfaces are coated with plated layers, theconductors have higher wettability with the conductive sealing memberused for sealing the lid 120 than that of the insulation substrate 110formed of, for example, a ceramic material. Thus, since the conductorsare not exposed, making of an unintentional short circuit or the likedue to flowing of the conductive sealing member to an unintentional partand incomplete hermetical sealing due to lack of the conductive sealingmember actually used for sealing are suppressed if the lid 120 isjoined.

If a conductive plate is embedded in the insulation substrate 110 asdescribed above, the strength of the insulation substrate 110 isimproved. In particular, since the expansion coefficient of theinsulation substrate 110 is different from those of the lid 120 andvarious types of wiring that are conductors, compared to the case where,for example, no metal conductor is disposed inside the frame portion 110a or a metal conductor is disposed inside but the conductor is a via orother structure having a thin columnar shape, the first conductiveportion 113 a reinforces the frame portion 110 a if the temperature ofthe wiring substrate 100 is varied. In particular, since the wiringconductor 113 (first conductive portion 113 a) is embedded such that thedistance between the inner side surface s1 and the wiring conductor 113increases at a boundary portion between the frame portion 110 a and thebase portion 110 b (near the bottom surface height h1), cracking or thelike at the boundary portion can be suppressed even if forces areexerted on the frame portion 110 a in various directions. Such forcesare generated in such a case where, for example, the lid 120 isconnected to the insulation substrate 110.

Next, an example of a method of manufacturing the insulation substrate110 that includes the wiring conductor 113 is described.

A through hole is provided in a ceramic green sheet that becomes theinsulation substrate 110 and a conductor is injected so as to form thethird conductive portion 113 c. The external connection conductors 116are formed on the second surface s12.

Metalized paste that becomes the first conductive portion 113 a and thesecond conductive portion 113 b is applied by printing (for example,screen printing) with a mask in an appropriate positional rangeincluding an upper portion of the third conductive portion 113 c on theceramic green sheet. Ceramic paste the material of which is the same asthat of the ceramic green sheet is applied by printing (for example,screen printing) with a mask in appropriate positional ranges that coverpart of the metalized paste.

The sheet to which the metalized paste and the ceramic paste are appliedis pressurized with a pressurizing tool having an irregular shapecorresponding to the accommodation section 111 and the frame portion 110a. This causes the metalized paste and the ceramic paste having beenapplied to be pressed down to the bottom surface height h1 of theaccommodation section 111 and part of the metalized paste correspondingto the second conductive portion 113 b to be interposed between thecoating layer 110 c and the ceramic green sheet and embedded. Theceramic green sheet, the metalized paste, and the ceramic paste aredeformed and filled into a recess of the pressurizing tool, thereby thepart corresponding to the first conductive portion 113 a interposedbetween the coating layer 110 c and the ceramic green sheet is embeddedand formed.

In this way, the coating layer 110 c and the ceramic green sheet areintegrated with each other, thereby providing the insulation substrate110 in which the metalized paste interposed between the coating layer110 c and the ceramic green sheet becomes the wiring conductor 113 notexposed other than in the first surface s11. The metalized paste appliedby printing to have a planar shape becomes the first conductive portion113 a and the second conductive portion 113 b that have curved surfaceshapes. Then, plating of the exposed surfaces, firing, attachment of theelectronic component 150, joining of the lid 120, and so forth areperformed according to need.

The electronic module 1 is manufactured by mounting the electronicdevice 10 on the module substrate 200. The external connectionconductors 116 of the electronic device 10 are joined to the electrodepads 201 of the module substrate 200 by using the joining members 210.

[Variations]

FIGS. 5A and 5B illustrate variations of the wiring conductor. FIG. 5Ais a sectional view illustrating an example of a first conductiveportion 1131 of a first variation. FIG. 5B is a perspective view of partof the insulation substrate 110 including a portion where sideconductors 1132, 1133 of a second variation are seen through theinsulation substrate 110 drawn transparently.

The first conductive portion 1131 of the first variation illustrated inFIG. 5A is connected to, for example, either or neither of the secondconductive portion 113 b and the third conductive portion 113 c. Thatis, although the first conductive portion 1131 is not electricallyconnected to the external connection conductor 116 and does not serve aspart of the electrical circuit, the first conductive portion 1131reinforces the frame portion 110 a. In this case, the first conductiveportion 1131 is not necessarily in contact with the frame-shapedmetalized layer 112. Here, although neither the second conductiveportion 113 b nor the third conductive portion 113 c exists in theillustration, the second conductive portion 113 b and the thirdconductive portion 113 c separated from the first conductive portion1131 may be provided. In this case, the second conductive portion 113 band the third conductive portion 113 c may be disposed at completelydifferent positions, or the second conductive portion 113 b may bedisposed close to an extended end of the first conductive portion 1131in the extension direction in the base portion 110 b. Even if the secondconductive portion 113 b and the third conductive portion 113 c areseparately disposed, strength may be appropriately increased againststress in desired directions by aligning the axial directions of thedisposed positions. Here, the first conductive portion 1131 is benttoward the outer side surface s2 of the frame portion 110 a at a portionnear a contact surface (near the first surface s11) where the firstconductive portion 1131 and the frame-shaped metalized layer 112 are incontact with each other. In this case, the following distance may beadopted as the “distance from the inner side surface of the recesssection on the first surface side to the wiring conductor”: that is, thedistance at a portion of the first conductive portion 1131 closest tothe inner side surface in a range on the first surface s11 side relativeto the central height of a range from the bottom surface height of therecess section to the first surface s11.

First conductive portions 1132, 1133 of the second variation illustratedin FIG. 5B are respectively disposed at two adjacent sides (the shortside and the long side) of the frame portion 110 a of the insulationsubstrate 110. That is, the insulation substrate 110 may include aplurality of the first conductive portions in the frame portion 110 a.The positions (sides) of the plurality of first conductive portions arenot particularly limited. The position where the wiring conductor 113and the frame-shaped metalized layer 112 are connected to each other inthe first surface s11 may be appropriately changed.

Neither the first conductive portion 1132 nor the first conductiveportion 1133 has a curved surface shape in the frame portion 110 a. Thefirst conductive portions 1132, 1133 are parallel to the inner sidesurfaces s1 of the frame portion 110 a forming the side surface of theaccommodation section 111. It is possible that only one of the firstconductive portions 1132, 1133 is connected to the frame-shapedmetalized layer 112 and the external connection conductor 116 (throughthe second conductive portion 113 b) or only one of the first conductiveportions 1132, 1133 is not connected to the frame-shaped metalized layer112 or the external connection conductor 116. Alternatively, it ispossible that all the first conductive portions 1132, 1133 are connectedto the frame-shaped metalized layer 112 and the external connectionconductors 116 or neither the first conductive portion 1132 nor thefirst conductive portion 1133 is connected to the frame-shaped metalizedlayer 112 or the external connection conductor 116.

As described above, the wiring substrate 100 of the present embodimentincludes the insulation substrate 110 including the recessedaccommodation section 111 in the first surface s11 and the electricalwiring structure (the connection pads 114, the through conductors 115,the external connection conductors 116, and so forth). The frame portion110 a that forms the side surfaces connecting the opened surface and thebottom surface of the accommodation section 111 of the insulationsubstrate 110 includes the plate-shaped first conductive portion 113 atherein.

If the conductive plate, that is, a metal plate or the like is disposedso as to be embedded in the frame portion 110 a having a thin shape asdescribed above, the frame portion 110 a is reinforced, and accordingly,deformation or the like occurring in joining the lid 120 can be reducedduring the manufacture. In particular, since the thermal expansioncoefficient of the ceramic material of the frame portion 110 a isdifferent from that of the metal conductors and the like forming thewiring structure, if the metal conductors are included in the frameportion 110 a formed of the ceramic material, such deformation can beeffectively reduced. Since the first conductive portion 113 a is notexposed, an unintentional short circuit is not made. Thus, the highlyreliable wiring substrate 100 in which the electronic component 150 canbe stably operated can be provided.

The first conductive portion 113 a has a curved surface shape. Thus, theinsulation substrate 110 (frame portion 110 a) can be more effectivelyreinforced in a larger stress direction.

The distance between the first conductive portion 113 a and the innerside surface s1 of the accommodation section 111 is greater at aposition of the bottom surface height h1 of the accommodation section111 than at a position on the first surface s11 side. Accordingly, thethickness of a root portion of the frame portion 110 a from the innerside surface s1 to the first conductive portion 113 a can be increasedwhile separating the first conductive portion 113 a from an angledportion on the outer peripheral side of the frame portion 110 a.Accordingly, the possibility of cracking at the root portion of theframe portion 110 a near the first conductive portion 113 a can befurther reduced even if forces are exerted on the frame portion 110 a invarious directions in, for example, joining the lid 120.

The first conductive portion 113 a is curved relative to the arbitrarytangent m 1 in the direction separating from the tangent m 1 toward theaccommodation section 111. Because of this form, the thickness betweenthe first conductive portion 113 a and the inner side surface s1 of theframe portion 110 a can be increased at a portion near the bottomsurface height h1 of the accommodation section 111. For example, in thecase where the first conductive portion 113 a is curved in the oppositedirection, even if the thickness at the bottom surface height h1 of theaccommodation section 111 is the same, the amount of reduction inthickness relative to the amount of change in position toward the firstsurface s11 increases. However, since the first conductive portion 113 ais curved in the direction described for the above-described embodiment,the amount of reduction in thickness relative to the amount of change inposition toward the first surface s11 can be reduced. Accordingly, ifthe first conductive portion 113 a is curved as described above, thethickness between the first conductive portion 113 a and the inner sidesurface s1 of the frame portion 110 a can be increased at a portion nearthe root portion of the frame portion 110 a. This can further reduce thepossibility of cracking at portions near the root of the frame portion110 a.

According to the wiring substrate 100 of the present embodiment, thedistance between the inner side surface s1 of the accommodation section111 and the first conductive portion 113 a gradually increases from thefirst surface s11 side toward a portion at the bottom surface height h1of the accommodation section 111. Accordingly, if forces are exerted onthe frame portion 110 a in various directions, stress exerted on aportion near the first conductive portion 113 a is spread and is notconcentrated in a particular position. This can further reduce thepossibility of cracking in the inner side surface s1 near the firstconductive portion 113 a throughout a range from the bottom surfaceheight h1 of the accommodation section 111 to the first surface s11side.

According to the wiring substrate 100 of the present embodiment, thedegree of inclination r of the first conductive portion 113 a withreference to the line v (normal line) perpendicular to the secondsurface s12 is greater than the degree of inclination of the inner sidesurface s1 of the accommodation section 111. Accordingly, in a structurein which the inner side surface s1 of the accommodation section 111 arenearly perpendicular to the second surface s12, the effects of reducingthe possibility of cracking as described above are produced. In thestructure in which the inner side surface s1 of the accommodationsection 111 is nearly perpendicular to the second surface s12, it isensured that the area of the accommodation section 111 from an openingend to the bottom surface is nearly uniform. This provides an advantagein that the electronic component 150 is easily mounted in theaccommodation section 111.

According to the wiring substrate 100 of the present embodiment, thebase portion 110 b forming the bottom surface of the accommodationsection 111 of the insulation substrate 110 includes the secondconductive portion 113 b therein. Thus, the base portion 110 b can besimilarly reinforced in addition to the frame portion 110 a.

In the wiring substrate 100 of the present embodiment, the firstconductive portion 113 a and the second conductive portion 113 b areconnected to each other. That is, if the first conductive portion 113 aand the second conductive portion 113 b are integrally formed, thewiring substrate 100 can be effectively reinforced.

According to the wiring substrate 100 of the present embodiment, theinsulation substrate 110 includes the external connection conductors 116outside the accommodation section 111, and the second conductive portion113 b is electrically connected to one of the external connectionconductors 116. Thus, the conductors themselves in the insulationsubstrate 110 can be used as wiring. The second conductive portion 113 bis grounded if the external connection conductor 116 is grounded. Thiscan effectively reduce influence of external noise on the electroniccomponent 150 disposed inside. In particular, if the second conductiveportion 113 b and the first conductive portion 113 a are connected toeach other, external noise can be more effectively blocked. If thesecond conductive portion 113 b also has a plate shape, the sectionalarea of the wiring conductor 113 is increased. Thus, electricalresistance of electrical circuitry including the case of grounding canbe suppressed.

According to the wiring substrate 100 of the present embodiment, thefirst conductive portion 113 a and the second conductive portion 113 bare continuous with each other to have a curved surface shape. Thisreduces the likelihood of forces being exerted in a concentrated manneron a connecting portion between the first conductive portion 113 a andthe second conductive portion 113 b. Thus, disconnection between thefirst conductive portion 113 a and the second conductive portion 113 band cracking or the like in the insulation substrate 110 along with thedisconnection can be avoided.

According to the wiring substrate 100 of the present embodiment, theframe-shaped metalized layer 112 disposed on the end surface on theopened surface side of the frame portion 110 a is provided, and thefirst conductive portion 113 a is electrically connected to theframe-shaped metalized layer 112 on the contact surface side of theframe-shaped metalized layer 112 in contact with the frame portion 110a. Thus, the first conductive portion 113 a is electrically connected tothe frame-shaped metalized layer 112 without being exposed at all.Accordingly, unnecessary short circuit can be avoided. This can prevent,in joining the lid 120 to the frame-shaped metalized layer 112, theoccurrences of problems with insulation caused by extending of theconductive sealing member from the frame-shaped metalized layer 112 andflowing of the conductive sealing member along the conductors. A viahole provided in the frame portion 110 a of related-art for connectingthe frame-shaped metalized layer 112 to the external connectionconductor 116 is not necessary. This drops need for a technique, time,and effort relating to improvement of positional accuracy for forming athrough hole in the thin frame portion 110 a. This can effectivelyreduce, for example, the likelihood of deformation due to lack ofstrength caused by formation of the via hole.

The electronic device 10 of the present embodiment includes theabove-described wiring substrate 100 and the electronic component 150that is disposed in the accommodation section 111 and connected to, forexample, the electrical wiring structure (the connection pads 114, thethrough conductors 115, the external connection conductors 116, and soforth). The strength of such an electronic device 10 can be improvedwhile the size of the electronic device 10 can be effectively accuratelyreduced in accordance with the size of the electronic component 150. Ifthe first conductive portion 113 a is also grounded, immunity againstexternal noise can be effectively improved even if the frame portion 110a has a small thickness.

The electronic module 1 of the present embodiment includes theabove-described electronic device 10 and the module substrate 200 towhich the electronic device 10 is connected. If such an electronicdevice 10 is used, the electronic component and circuits can be moreefficiently disposed on the module substrate 200. Accordingly, the sizeand weight of the electronic module 1 can be reduced and the functionsof the electronic module 1 can be improved.

The above-described embodiment is exemplary, and various changes can bemade to the embodiment.

For example, the length of the first conductive portion 113 a in adirection along the peripheral direction of the frame portion 110 a issmaller than the length of the frame portion 110 a in the abovedescription. However, this length of the first conductive portion 113 amay be close to the length of the frame portion 110 a.

The shape of the accommodation section 111 is not necessarily a cuboid.The shape of the accommodation section 111 in plan view may be a polygonother than a quadrangle or a quadrilateral other than a cuboid. The sidesurfaces of the accommodation section 111 formed by the frame portion110 a, the bottom surface of the accommodation section 111 formed by thebase portion 110 b, or both the side surfaces and the bottom surface ofthe accommodation section 111 may be curved instead of being flat. Theside surfaces may have a tapered shape or have a step disposed partway.

The numbers, disposition, and positional relationships of the connectionpads 114, the external connection conductors 116, and wiring linesconnecting these may be appropriately changed in accordance with theelectronic component 150 accommodated in the accommodation section 111.Also, the shape of the connection pads 114 may be changed.

According to the above-described embodiment, the description has beenmade with the example in which the insulation substrate 110 includes asingle accommodation section 111 in a single surface. However, aplurality of accommodation sections may be provided in a single surface.The accommodation sections may be disposed in a plurality of (such as,for example, front and rear surfaces) surfaces (a plurality of firstsurfaces).

According to the above-described embodiment, it has been described thatthe wiring substrate 100 and the lid 120 have cuboid shapes. However,the wiring substrate 100 and the lid 120 may have other shapes than thecuboid shapes. For the cuboid, vertices, edges, or the like may beprovided with notches.

Although the lid 120 is included in the wiring substrate 100 in thedescription of the above-described embodiment, the lid 120 may be adifferent unit from the wiring substrate 100.

Although the first conductive portion 113 a and the second conductiveportion 113 b have respective plate shapes according to theabove-described embodiment, only the first conductive portion 113 a mayhave a plate shape. The base portion 110 b, which has a sufficient areacompared to the frame portion 110 a, is not necessarily a plate-shapedconductor to obtain sufficient strength. That is, the second conductiveportion 113 b may have a thick linear structure. If the secondconductive portion 113 b is not provided, the first conductive portion113 a may extend downward so as to be connected to the externalconnection conductor 116.

If the first conductive portion 113 a has such a shape that the distancebetween the first conductive portion 113 a and the inner side surface s1of the accommodation section 111 is greater at a position of the bottomsurface height h1 of the accommodation section 111 than at a position onthe first surface s11 side, the first conductive portion 113 a may havea thick linear structure instead of a plate shape. Only with theabove-described shape, cracking at a portion near the root of the frameportion 110 a can be suppressed and the strength of the structure can beimproved compared to the related-art structure.

According to the above-described embodiment, the structure is describedin which the distance between the first conductive portion 113 a of thewiring conductor 113 and the inner side surface s1 of the frame portion110 a gradually increases from the first surface s11 toward the bottomsurface height h1 of the accommodation section 111 and the firstconductive portion 113 a of the wiring conductor 113 is curved. As thesecond variation, the structure is described in which the firstconductive portion 113 a is perpendicular to the second surface s12.However, the distance between the wiring conductor 113 and the innerside surface s1 of the frame portion 110 a may be increased in a singlestep or a plurality of steps, and the first conductive portion 113 a isnot necessarily curved.

Formation of the first conductive portion 113 a is not limited to theabove-described method of manufacturing. The first conductive portion113 a may be formed by any method. If the first conductive portion 113 ais manufactured by any of a variety of method of manufacturing, thefirst conductive portion 113 a does not necessarily have a curvedsurface shape. In addition, the first conductive portion 113 a and thesecond conductive portion 113 b are not continuous with each other in acurved surface shape.

In addition to the above description, the specific structures describedfor the above-described embodiment and the specific details such asshapes, disposition, and positional relationships of the specificstructures can be appropriately changed without departing from the gistof the present disclosure.

1. A wiring substrate comprising: an insulation substrate that comprisesa recess section in a first surface, a frame portion that forms a sidesurface which connects an opened surface of the recess section and abottom surface of the recess section to each other, and a base portionthat forms the bottom surface; and an electrical wiring structure thatis on and inside the base portion, wherein the frame portion comprises afirst conductive portion having a plate shape in the frame portion, andextending from the first surface to the base portion through the frameportion, and wherein the first conductive portion is coated with aninsulation body.
 2. The wiring substrate according to claim 1, whereinthe first conductive portion has a curved surface shape.
 3. The wiringsubstrate according to claim 1, wherein a distance between the firstconductive portion and an inner side surface of the recess section isgreater at a bottom surface height of the recess section than on a firstsurface side.
 4. The wiring substrate according to claim 3, wherein thefirst conductive portion is curved, relative to a tangent that isarbitrarily selected, in a direction separating from the tangent towardthe recess section.
 5. The wiring substrate according to claim 3,wherein the distance between the first conductive portion and the innerside surface of the recess section gradually increases from the firstsurface side toward a portion at the bottom surface height of the recesssection.
 6. The wiring substrate according to claim 3, wherein a degreeof inclination of the first conductive portion and a line perpendicularto a second surface opposite the first surface of the insulationsubstrate relative to each other is greater than a degree of inclinationof the inner side surface of the recess section and a line perpendicularto the second surface relative to each other.
 7. The wiring substrateaccording to claim 1, wherein the base portion comprises a secondconductive portion in the base portion.
 8. The wiring substrateaccording to claim 7, wherein the first conductive portion and thesecond conductive portion are connected to each other.
 9. The wiringsubstrate according to claim 7, wherein the insulation substratecomprises an external connection conductor disposed outside the recesssection, and wherein the second conductive portion is electricallyconnected to the external connection conductor.
 10. The wiring substrateaccording to claim 8, wherein the first conductive portion and thesecond conductive portion are continuous with each other and form acurved surface.
 11. The wiring substrate according to claim 10, furthercomprising: a frame-shaped conductive layer disposed on an end surfaceon the opened surface side of the frame portion, wherein the firstconductive portion is electrically connected to the frame-shapedconductive layer on a contact surface side of the frame-shapedconductive layer in contact with the frame portion.
 12. An electronicdevice comprising: the wiring substrate according to claim 1; and anelectronic component that is disposed in the recess section and that isconnected to the electrical wiring structure.
 13. An electronic modulecomprising: the electronic device according to claim 12; and a modulesubstrate to which the electronic device is connected.
 14. The wiringsubstrate according to claim 1, wherein the first conductive portion iscurved, relative to a tangent that is arbitrarily selected, in adirection separating from the tangent toward the recess section.